The effect of delayed autogenous bone grafting on the healing of diaphyseal defects in a canine model.

Bone grafting of osseous defects is often delayed to minimize the risk of infection, however, the effect of this delay on defect healing is not clear. Unilateral oblong unicortical diaphyseal femoral defects (30 x 4.5 mm) were created in 3 groups of 18 adult canines that were grafted with autogenous bone immediately, at 2 weeks, and at 6 weeks. After an 8-week healing period, paired femurs, h consisted of defect versus intact specimens, were assessed by biomechanical testing and microradiography. No differences were demonstrated biomechanically or radiographically between the healing defects with immediate versus delayed bone grafting. This study suggests that within the first 6 weeks postoperatively osseous defects can be grafted with autologous bone without adversely affecting bone graft incorporation.